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Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors

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Petroleum Science 2023年第4期20卷 2468-2478页

作者： Bo Yao Hao-Ran Zhu Bao-Dong Yan Chuan-Xian Li Fei Yang Guang-Yu Sun Hong-Bo Zeng College of Pipeline and Civil Engineering China University of PetroleumQingdaoShandong266580People's Republic of China Department of Chemical and Materials Engineering University of AlbertaEdmontonABT6G 1H9Canada School of Petroleum Engineering Changzhou UniversityChangzhouJiangsu213164People's Republic of China China Oil&Gas Pipeline Network Corporation Beijing100020China

This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax *** is found that there is little difference in wax precipitation exothermic characteristics of crude oils at different T_(pre),as well as the wax crystal solubility coefficient in the temperature range of 25-30℃.For the undoped crude oil,the flowability after wax precipitation gets much improved and the wax deposition is alleviated as T_(pre)*** T_(pre)=50℃,the viscosity and wax deposition rate of crude oil adding wax inhibitors are higher than those of the undoped crude *** the T_(pre)increases to 60,70,and 80℃,the flowability of the doped crude oil are largely improved and the wax deposition is suppressed with the T_(pre)increase,but the wax content of wax deposit increases *** is speculated that,on the one hand,the T_(pre)increase helps the dispersion of asphaltenes into smaller sizes,which facilitates the co-crystallization with paraffin waxes and generates more aggregated wax crystal *** weakens the low-temperature gel structure and increases the solid concentration required for the crosslink to form the wax *** the other hand,the decrease in viscosity increases the diffusion rate of wax molecules and accelerates the aging of wax *** experimental results have important guiding significance for the pipeline transportation of doped crude oils.

关键词： Pre-heating treatment Wax inhibitor flowability Wax deposition Waxy crude oil

Spent coffee grounds as a renewable source of energy: An analysis of bulk powder flowability

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Particuology 2019年第2期17卷 92-100页

作者： L. Massaro Sousa M.C. Ferreira Drying Center for Pastes Suspensions and Seeds. Chemical Engineering Department Federal University of Sao Carlos. P.O. Box 676 13565-905 Sao Carlos Brazil

The main use for spent coffee grounds (SCG) produced in the soluble coffee industry is thermal energy generation in the industry itself. The SCG are processed using operations that are strongly dependent on powder flow behavior. In this study, we evaluated two classical flowability in dices of non-consolidated SCG powders: the angle of repose (AoR), and the Hausner ratio (HR). The influences of the mean particle diameter, particle size distribution (PSD), and water content on the AoR and HR values of SCG were analyzed for powders with a mean particle size range of 225-550 μm. For powders with a mean particle size close to 350 μm and for mixtures containing more than 40% fine particles, the HR (>1.35) and AoR (>45 °) values were characteristic of poor flowability. The AoR was sensitive to the powder PSD, and powders with similar mean particle sizes had higher AoR values when the PSD was larger. For powders w让h water contents up to 50%, the flowability indices were not greatly affected by the water content. A modified linear-mixture packing model was used to predict the packed bed void fractions for binary and ternary mixtures of the three base powders. The model was used to construct a ternary diagram to estimate the HR values of the mixtures. An equation was fitted to correlate HR and AoR. The proposed diagram and the equation provide insight into flow behavior and could be used for process design of industrial plants that handle SCG.

关键词： Spent coffee ground Biomass flowability Hausner ratio Angle of repose

Effect of silane coupling agents on flowability and compressibility of compound for bonded NdFeB magnet

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Journal of Rare Earths 2022年第5期40卷 772-777,I0004页

作者： Xiaowei Zhang Zilong Wang Tianhao Li Shengjie Zhu Dunbo Yu Wenlong Yan Yang Luo National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Based on the difference of the Y-terminal functional group of the silane coupling agent(Y-Si(X)_(3)),four different silane coupling agents were employed to pretreat the surface of the NdFeB *** effects of silane coupling agents on the flowability and compressibility of compounds for preparing bonded NdFeB magnets were *** is indicated that compounds pretreated by silane coupling agents have weaker friction and meshing *** apparent density is increased by 0.3 g/cm^(3 )compared with the compound without silane coupling agent,and the radial crushing strength is significantly increased by about 3-4 *** addition,the epoxy resin is more evenly distributed on the surface of the compounds treated by silane coupling agents observed by scanning electron microscopy,and some agglomerated particles are ***,the compressibility of compounds with silane coupling agents is significantly improved due to the fact that hardening exponents are ***,the addition of silane coupling agents has almost no effect on the magnetic properties of bonded *** special energy was used to manifest the flowability of magnetic powder particles representing the macroscopic performance of the force between powder particles,providing a new direction for the study of the interface compatibility of two-phase or multiphase composite materials.

关键词： Bonded NdFeB magnets Silane coupling agent flowability Special energy Compressibility Rare earths

Characterization of the flowability dynamics of granular material flowing down a narrow channel

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Particuology 2020年第6期18卷 72-82页

作者： Ningsheng Wang Haifeng Lu Jianliang Xu Xiaolei Guo Haifeng Liu Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education East China University of Science and TechnologyP.O.Box 272Shanghai 200237China Shanghai Engineering Research Center of Coal Gasification East China University of Science and TechnologyP.O.Box 272Shanghai 200237China Ningbo Ruiling Institute for Energy and Environment Solutions Ningbo 315500China

The flowability of granular material is commonly determined from shear cell tests,but in the real world,the granular flow is quite different in many *** this paper,the flowabilities in a narrow channel of five different granular materials were *** flow parameters of the granular flows were determined to classify the flowabil让*** flow surface velocities and flow heights and thicknesses were measured,and it was found that the mean shear rates in the linear portions of the velocity profiles in crease with both flow rates and incli nation.A universal parameter,the ratio of the sine of the inclin ation to the shear rate in the linear part of the velocity profile,is proposed as a *** constant is independent of particle *** addition,a flowability parameter,the ratio of the mean shear rate to the cosine of the inclination,is proposed to characterize the friction between the particles in the flowing granular material.

关键词： Dynamic characterization Granular flow Velocity profile flowability Channel

A study on the flowability of gas displacing water in low-permeability coal reservoir based on NMR technology

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Frontiers of Earth Science 2020年第4期14卷 673-683页

作者： Minfang Yang Zhaobiao Yang Bin Sun Zhengguang Zhang Honglin Liu Junlong Zhao Department of Unconventionals Research Institute of Petroleum Exploration and DevelopmentPetroChinaLangfang065007China Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process(Ministry of Education) China University of Mining and TechnologyXuzhou221008China School of Resource and Geosciences China University of Mining and TechnologyXuzhou221116China

flowability of gas and water through low-permeability coal plays crucial roles in coalbed methane(CBM)recovery from coal *** better understand this phenomenon,experiments examining the displacement of water by gas under different displacement pressures were systematically carried out based on nuclear magnetic resonance(NMR)technology using low-permeability coal samples of medium-high coal rank from Yunnan and Guizhou,*** results reveal that both the residual water content(W_(r))and residual water saturation(S_(r))of coal gradually decrease as the displacement pressure(P)*** P is 0-2 MPa,the decline rates of W_(r) and S_(r) are fastest,beyond which they slow down *** samples with higher permeability exhibit higher water flowability and larger decreases in W_(r) and S_(r).Compared with medium-rank coal,high-rank coal shows weaker fluidity and a higher proportion of irreducible *** relationship between P and the cumulative displaced water content(W_(c))can be described by a Langmuir-like equation,W_(c)=WLP/(PL+P),showing an increase in W_(c) in coal with an increase in *** the low-pressure stage from 0 to 2 MPa,W_(c) increases most rapidly,while in the high-pressure stage(P>2 MPa),W_(c) tends to be *** minimum pore diameter(d′)at which water can be displaced under different displacement pressures was also *** d′value decreases as P increases in a power relationship;i.e.,d′the coal gradually decreases with the gradual increase in ***,the d′values of most of the coal samples are close to 20 nm under a P of 10 MPa.

关键词： coalbed methane low-permeability coal reservoir NMR gas displacing water flowability pore size

Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil Manna Deepa Devapal Sharad Chandra Sharma Jyotsna Dutta Majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT Mesra RanchiJharkhandIndia Department of Metallurgical and Materials Engineering IIT KharagpurWest BengalIndia Vikram Sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron Microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of Hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured Hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(Hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： Mechanical milling Microstructure Process control agent(PCA) CoNiCrAlY Toluene Stearic acid flowability

Characterisation of flowability of cohesive powders by testing small quantities of weak compacts

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Particuology 2008年第4期6卷 282-285页

作者： Ali Hassanpour Mojtaba Ghadiri Institute of Particle Science and Engineering University of LeedsLeeds LS2 9JTUnited Kingdom

Characterisation of flowability of small quantities of cohesive powders is of great industrial interest, particularly for the pharmaceutical sec- tors, where a limited amount of material is available or the material is not easily accessible. In this paper, ball indentation on a powder bed is evaluated for flow characterisation of small quantities of cohesive powders at low levels of consolidation pressures. In parallel, the bulk powder is subjected to the common test method of unconfined direct compression. Analogous to indentation hardness testing, for which the indentation pressure is related to the flow stress, a constraint factor (C) is defined relating the unconfined yield stress and indentation pres- sure. The constraint factors for the test powders have been evaluated, enabling an easy method to characterize the flow behaviour of cohesive powders.

关键词： flowability Cohesive powder Indentation on powder bed Constraint factor

Mechanical Properties and flowability of High Strength Concrete Incorporating Ground Granulated Blast-furnace Slag

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Journal of Wuhan University of Technology(Materials Science) 2001年第3期16卷 42-45页

作者：姚武 State Key Lab. of Concrete Mat. Res. Tongji University Shanghai 200092 China

The high strength concrete(HSC)was produced by partially replacingthe normal portland cement with special ground granulatedblast-furnace slag(GGBS)ranging up to 60/100. The effects of the GGBSon the flowabilityand mechanical properties of HSC were studied. Thehydration process and microstructure char- acteristics wereinvestigated by X-ray diffraction(XRD)and scanning microscopy(SEM),respectively. The test results indicate that the GGBS has especiallysupplementary effect on water reducing and excellent property Ofbetter control of lump loss.

关键词： high strength concrete mechanical property flowability

The flowability of Ground Powders and the Comminuting Mechanism of Mills

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Journal of Wuhan University of Technology(Materials Science) 2004年第4期19卷 13-16页

作者：张佑林 Wuhan University of Technology

The ground powders with the same particle size distribution and the same mean particle diameter were prepared by five different types of mills. The flowability index (FI) and the particle shape indices, namely, Wadell's working sphericity Ψ W and circularity Ψ C, of five kinds of test powders were measured. The effect of the comminuting mechanisms on the flowability of ground powders was investigated, and the relationship between the flowability of ground powders and the particle shape indices was analyzed. The experimental results show that the ground powders obtained by collision have irregular particle shapes and smooth surfaces, showing a high flowability. On the other hand, though the particle obtained by grinding is close to a spherical particle, but it has a rugged surface, and shows a bad flowability. Furthermore, the flowability index is more correlated with the circularity than the working sphericity is. This means that the surface roughness is more effective in determining the flowability of powders than the roundness is.

关键词： powder flowability comminuting mechanism particle shape